Waveguide circulators typically have a waveguide housing that defines a central cavity and three waveguide arms extending from the central cavity. A ferrite element is located in the central cavity to increase coupling between the arms. The central cavity and three waveguide arms are typically defined by a floor, a ceiling, and a plurality of sidewalls. In such waveguide circulators the dimensions of the central cavity and three waveguide arms are based on the desired frequency range of operation. The height between the floor and ceiling is constant throughout the central cavity and the three waveguide arms provide high quality coupling between the waveguide arms and the central cavity and enable easier manufacturing.